fileioc.h

#include <fileioc.h>

The fileioc library provides access to OS variables such as AppVars, Programs, Lists, and Strings.

AppVars are special types of variables that can be used to store any arbitrary data, and are utilized by the CE toolchain to provide data storage beyond what can be compiled into a program. AppVars may store things like save states, sprites, and user configurations. Because the program context is destroyed when a program returns to the OS, AppVars can be used to store data between program launches.

The OS stores variables in either RAM or archive (aka flash) memory. RAM memory is volatile and is cleared whenever the calculator is reset, whereas archive memory provides a more permanent storage for variables. However, variables can only be written to while in RAM as the calculator’s security measures do not provide a way to directly write to the archive. The function ti_SetArchiveStatus can be used to move a variable between the archive and RAM.

The function ti_Open and ti_OpenVar can be used to access AppVars and other OS variables respectively. They return an opaque handle value that is passed to the other functions available in the library.

API Documentation

API Documentation 

Author: Matt “MateoConLechuga” Waltz

Defines

TI_PRGM_TYPE: Unprotected program.

TI_PPRGM_TYPE: Protected program.

TI_TPRGM_TYPE: Temporary program.

TI_APPVAR_TYPE: AppVar.

TI_STRING_TYPE: String.

TI_EQU_TYPE: Equation.

TI_ANS_TYPE: Ans.

TI_REAL_LIST_TYPE: Real variable list.

TI_CPLX_LIST_TYPE: Complex variable list.

TI_REAL_TYPE: Real variable.

TI_CPLX_TYPE: Complex variable.

TI_MATRIX_TYPE: Matrix variable.

TI_MAX_SIZE: Maximum variable size.

Functions

uint8_t ti_Open(const char *name, const char *mode)

Opens an AppVar for reading, writing, and/or appending.

AppVars may be stored in either the archive (aka flash memory), or in RAM. Depending on the mode used to open the AppVar it may be moved from archive memory into RAM.

mode	Description
”r”	Read mode. If the AppVar does not exist `0` is returned. The AppVar is not moved from its storage location.
”w”	Write mode. Deletes any existing AppVar and creates the AppVar in RAM.
”a”	Append mode. The AppVar is created if it does not exist. If the AppVar is stored in the archive it is moved to RAM.
”r+”	Read/Write mode. If the AppVar does not exist `0` is returned. If the AppVar is stored in the archive it is moved to RAM.
”w+”	Write/Read mode. Deletes any existing AppVar and creates the AppVar in RAM.
”a+”	Append/Read mode. The AppVar is created if it does not exist. If the AppVar is stored in the archive it is moved to RAM.

Parameters

name – [in] Name of AppVar to open.
mode – [in] Documented in the above table.

Returns

AppVar variable handle, or 0 (zero) on error.

uint8_t ti_OpenVar(const char *name, const char *mode, uint8_t type)

Opens a variable for reading, writing, and/or appending.

Variables may be stored in either the archive (aka flash memory), or in RAM. Depending on the mode used to open the variable it may be moved from archive memory into RAM.

mode	Description
”r”	Read mode. If the variable does not exist `0` is returned. The variable is not moved from its storage location.
”w”	Write mode. Deletes any existing variable and creates the variable in RAM.
”a”	Append mode. The variable is created if it does not exist. If the variable is stored in the archive it is moved to RAM.
”r+”	Read/Write mode. If the variable does not exist `0` is returned. If the variable is stored in the archive it is moved to RAM.
”w+”	Write/Read mode. Deletes any existing variable and creates the variable in RAM.
”a+”	Append/Read mode. The variable is created if it does not exist. If the variable is stored in the archive it is moved to RAM.

Parameters

name – [in] Name of variable to open.
mode – [in] Documented in the above table.
type – [in] Variable type.

Returns

Variable handle, or 0 (zero) on error.

int ti_Close(uint8_t handle)

Closes an open AppVar/variable handle.

This must be performed for every ti_Open or ti_OpenVar call.

Parameters: handle – [in] AppVar/variable handle.
Returns: 0 (zero) on error.

char *ti_Detect(void **vat_ptr, const char *detect_string)

Locates AppVars stored in archive and RAM.

This function searches for AppVars whose data section begins with a specific string. The null terminator of the string is not included in the search.

vat_ptr should be set to NULL to begin a search, and is updated with each call.

char *var_name;
void *vat_ptr = NULL;

while ((var_name = ti_Detect(&vat_ptr, "my_data")))
{
    // do something with var_name or vat_ptr
}

Note

If the return value is NULL, there are no more variables to find.

Parameters

vat_ptr – [in] Current offset in the VAT.
detect_string – [in] String to search for (NULL to search for all).

Returns

The AppVar name. This should be duplicated to another buffer as subsequent calls of this function change the name stored at the returned pointer’s address.

char *ti_DetectVar(void **vat_ptr, const char *detect_string, uint8_t var_type)

Locates variables stored in archive and RAM.

This function searches for variables whose data section begins with a specific string. The null terminator of the string is not included in the search.

vat_ptr should be set to NULL to begin a search, and is updated with each call.

char *var_name;
void *vat_ptr = NULL;

while ((var_name = ti_DetectVar(&vat_ptr, "my_data", TI_PRGM_TYPE)))
{
    // do something with var_name or vat_ptr
}

Note

If the return value is NULL, there are no more variables to find.

Parameters

vat_ptr – [inout] Current offset in the VAT.
detect_string – [in] String to search for (NULL to search for all).
var_type – [in] Type of variable to detect.

Returns

The variable name. This should be duplicated to another buffer as subsequent calls of this function change the name stored at the returned pointer’s address.

char *ti_DetectAny(void **vat_ptr, const char *detect_string, uint8_t *var_type)

Locates any variables stored in archive and RAM.

This function searches for variables whose data section begins with a specific string. The null terminator of the string is not included in the search.

vat_ptr should be set to NULL to begin a search, and is updated with each call.

uint8_t var_type;
char *var_name;
void *vat_ptr = NULL;

while ((var_name = ti_DetectAny(&vat_ptr, "my_data", &var_type)))
{
    if (var_type == TI_PRGM_TYPE || var_type == TI_PPRGM_TYPE)
    {
        // do something with var_name or vat_ptr
    }
}

Note

If the return value is NULL, there are no more variables to find.

Parameters

vat_ptr – [inout] Current offset in the VAT.
detect_string – [in] String to search for (NULL to search for all).
var_type – [out] Type of variable found.

Returns

The variable name. This should be duplicated to another buffer as subsequent calls of this function change the name stored at the returned pointer’s address.

size_t ti_Write(const void *data, size_t size, size_t count, uint8_t handle)

Writes data to an AppVar/variable handle.

Parameters

data – [in] Pointer to data structure(s).
size – [in] Size (in bytes) of a single data structure.
count – [in] Number of data structures to write.
handle – [in] AppVar/variable handle.

Returns

Number of data structures written; equals count on success.

size_t ti_Read(void *data, size_t size, size_t count, uint8_t handle)

Reads data from an AppVar/variable handle.

Parameters

data – [out] Pointer to data structure(s).
size – [in] Size (in bytes) of a single data structure.
count – [in] Number of data structures to write.
handle – [in] AppVar/variable handle.

Returns

Number of data structures written; equals count on success.

int ti_PutC(char ch, uint8_t handle)

Writes a character to an AppVar/variable handle.

Parameters

ch – [in] Character to write.
handle – [in] AppVar/variable handle.

Returns

EOF on error, or ch.

int ti_GetC(uint8_t handle)

Reads a character from an AppVar/variable handle.

Parameters: handle – [in] AppVar/variable handle.
Returns: EOF on error, or a valid character.

int ti_Seek(int offset, unsigned int origin, uint8_t handle)

Seeks to an offset in the file.

origin	Description
SEEK_SET (`0`)	Seek from beginning of AppVar/variable.
SEEK_CUR (`1`)	Seek from current AppVar/variable offset.
SEEK_END (`2`)	Seek from end of AppVar/variable.

Parameters

offset – [in] Number of bytes to offest from (can be negative).
origin – [in] Documented in the above table.
handle – [in] AppVar/variable handle.

Returns

EOF on failure.

int ti_Rewind(uint8_t handle)

Seeks to the start of an AppVar/variable’s data.

Functionally equivalent to ti_Seek(0, SEEK_SET, handle)

Parameters: handle – [in] AppVar/variable handle.
Returns: EOF on failure.

uint16_t ti_Tell(uint8_t handle)

Gets the current data offset from the start of an AppVar/variable.

Parameters: handle – [in] AppVar/variable handle.
Returns: The current data offset from the start of the AppVar/variable.

uint16_t ti_GetSize(uint8_t handle)

Gets the size of an AppVar/variable.

Parameters: handle – [in] AppVar/variable handle.
Returns: The size of the AppVar/variable.

int ti_Resize(size_t size, uint8_t handle)

Resizes an AppVar/variable.

Parameters

handle – [in] AppVar/variable handle.
size – [in] New AppVar/variable size.

Returns

Resized size on success, 0 on failure, or -1 if the AppVar/variable cannot be opened.

int ti_IsArchived(uint8_t handle)

Checks if an AppVar/variable is stored in archive memory.

Parameters: handle – [in] AppVar/variable handle.
Returns: 0 if the AppVar/variable is not in the archive.

int ti_SetArchiveStatus(bool archive, uint8_t handle)

Moves an AppVar/variable between archive or RAM storage.

archive	Description
true	Store AppVar/variable in archive.
false	Store AppVar/variable in RAM.

Warning

Archiving a variable can cause a garbage collection cycle. You should use ti_SetGCBehavior to catch this event.

Parameters

archive – [in] Documented in the above table.
handle – [in] AppVar/variable handle.

Returns

0 on failure.

int ti_Delete(const char *name)

Deletes an AppVar.

Parameters: name – [in] AppVar name.
Returns: 0 on failure.

int ti_DeleteVar(const char *name, uint8_t type)

Deletes a variable.

Parameters

name – [in] Variable name.
type – [in] Variable type.

Returns

0 on failure.

char *ti_GetTokenString(void **read_pointer, uint8_t *token_len, unsigned int *str_len)

Gets the string used for displaying a TI token.

The TI calculators encode programs and other variables in “tokens”, which are either 1 or 2 bytes in length. For example, the token :code:0x21 corresponds to the string :code:mean( in TI-BASIC programs. This allows program size to be reduced as the whole string is not stored - but requires additional decoding in order to resolve the token’s string representation.

Note

read_pointer is automatically updated to point to the next token, incremented by the value of token_len.

Parameters

read_pointer – [inout] Address of pointer to data to read.
token_len – [out] Pointer to variable to hold length of the token, used for determining the next read location (Can be NULL if unused).
str_len – [out] Pointer to variable to hold length of resulting string (Can be NULL if unused). The returned string is static, and should be copied to another buffer as needed if it needs to be preserved across function calls.

Returns

A pointer to a null-terminated string used for displaying a TI token.

void *ti_GetDataPtr(uint8_t handle)

Gets a direct data pointer to the current offset in an AppVar/variable.

This may be used for direct reading/writing without the need for an extra copy. It is easily prone to memory corruption if not used correctly, so use at your own risk.

Note

If the AppVar is in RAM, the direct pointer can be used to read/modify its contents directly, with the caveat that the AppVar must be large enough to consume any writes. If the AppVar is in the archive, direct reading is possible but writes will lead to a system reset.

Warning

This function is potentially unsafe to use as variables may be shifted around in memory, causing this pointer to become invalid and potentially corrupt memory. Avoid creating, deleting, resizing, or changing the storage location any variables while this pointer is being actively used.

Parameters: handle – [in] AppVar/variable handle.
Returns: Pointer to AppVar/variable data.

void *ti_GetVATPtr(uint8_t handle)

Gets a pointer to the VAT entry of an AppVar/variable.

Note

If the variable is in RAM, the direct pointer can be used to read/modify its contents directly, with the caveat that the AppVar must be large enough to consume any writes. If the AppVar is in the archive, direct reading is possible but writes will lead to a system reset.

Warning

This function is potentially unsafe to use as variables may be shifted around in memory, causing this pointer to become invalid and potentially corrupt memory. Avoid creating, deleting, resizing, or changing the storage location any variables while this pointer is being actively used.

Parameters: handle – [in] AppVar/variable handle.
Returns: VAT location of the variable.

void ti_GetName(char *name, uint8_t handle)

Gets the AppVar/variable name of an already opened handle.

Parameters

name – [in] Buffer to store name, must be at least 10 bytes in sizew.
handle – [in] AppVar/variable handle.

uint8_t ti_Rename(const char *old_name, const char *new_name)

Renames an AppVar.

Warning

It is hazardous to rename an open AppVar. Close the AppVar before renaming.

Parameters

old_name – [in] Old name of AppVar.
new_name – [in] New name of AppVar.

Returns

0 if success, 1 if AppVar already exists, 2 any other error occurs.

uint8_t ti_RenameVar(const char *old_name, const char *new_name, uint8_t type)

Renames a variable.

Warning

It is hazardous to rename an open variable. Close the variable before renaming.

Parameters

old_name – [in] Old name of variable.
new_name – [in] New name of variable.
type – [in] Type of variable.

Returns

0 if success, 1 if variable already exists, 2 any other error occurs.

uint8_t ti_SetVar(uint8_t type, const char *name, const void *data)

Stores data or values to an OS variable.

Parameters

type – [in] Variable type.
name – [in] Variable name.
data – [in] Data to set variable to.

Returns

0 if success.

uint8_t ti_StoVar(uint8_t type_to, const char *to, uint8_t type_from, const char *from)

Stores an OS variable to another variable.

Parameters

type_to – [in] Variable type to store data to.
to – [in] Variable name to store data to.
type_from – [in] Variable type to get data from.
from – [in] Variable name to get data from.

Returns

0 if success.

uint8_t ti_RclVar(uint8_t type, const char *name, void **data)

Recalls a OS variable.

Note

data_struct is set to the variable’s data.

Parameters

type – [in] Variable type.
name – [in] Variable name.
data – [out] Address of pointer to variable structure.

Returns

0 if success.

bool ti_ArchiveHasRoom(uint24_t num_bytes)

Checks to see if there is room in the archive for storing num_bytes, without needing to execute a Garbage Collect.

Parameters: num_bytes – [in] Number of bytes to be stored to the archive.
Returns: true if the bytes can be stored to the archive without a Garbage Collect.

void ti_SetGCBehavior(void (*before)(void), void (*after)(void))

Set routines to run before and after a garbage collect would be triggered.

A garbage collect is used to free up space in archive memory by reorganizing archive variable storage and removing variables marked for deletion. The OS is required to request the user if they want to perform the operation, and this request may be triggered any time a variable is moved to archive memory. This function is used to set up callbacks that are triggered when this event occurs.

The OS prompt requires the LCD to be in the standard 16-bit color mode, so if graphx or custom LCD behavior is being used gfx_End should be used to restore the OS to its default state in the routine run before garbage collection.

In the after garbage collection rotuine, the LCD state can be restored (using gfx_Begin or similar as appropriate), as well as potentially reloading cached variable pointers created with ti_GetDataPtr.

Parameters

before – [in] Routine to run before a garbage collect. NULL sets it to do nothing.
after – [in] Routine to run following a garbage collect. NULL sets it to do nothing.

fileioc.h

API Documentation

API Documentation 